Dear FS-Experts
We examined longitudinal t1-based data and used the -long pipeline and
mri_glmfit for testing time effects.
Now for a more powerful statistical analysis we're trying to set up LME for our
data but we struggle while adapting from the tutorials cmd's.
##Problem:
We currently struggle with building the CM that compares differences in
cortical thicknes between the 2 time points and acts kind of a paired t-test.
Could any of you experts might help us setting up the correct parameters for
our analysis?
##Basics:
- 23 Pre/Post Subjects already processed through the longitudinal pipeline
- 2 time points
- Comparison of mass univariate data
Our qdec.table.dat consists of 5 columns:
1.) fsid
2.) fsid-base
3.) time
4.) group
5.) age
##Cmd History:
[Y,mri] = fs_read_Y('/Subjects/LME/lme_setup23/lh.sad23.thickness_sm10.mgh');
lhsphere = fs_read_surf('/Subjects/LME/lme_setup23/lh.sphere.reg');
lhcortex = fs_read_label('/Subjects/LME/lme_setup23/lh.cortex.label');
Qdec_total = fReadQdec('/Subjects/LME/lme_setup23/qdec.table.dat');
Qdec_fsidbase = rmQdecCol(Qdec_total,1);
sID = Qdec_fsidbase(2:end,1);
Qdec_time = rmQdecCol(Qdec_fsidbase,1);
M = Qdec2num(Qdec_time);
[Msort,Ysort,ni] = sortData(M,1,Y,sID);
X = [ones(length(Msort),1) Msort];
[theta0,residuals] = lme_mass_fit_EMinit(X,[1],Ysort,ni,lhcortex);
[regions,RgMeans] = lme_mass_RgGrow(lhsphere,residuals,theta0,lhcortex);
lhstats = lme_mass_fit_Rgw(X,[1],Ysort,ni,theta0,regions,lhsphere);
F_lhstats = lme_mass_F(lhstats,CM);
dvtx = lme_mass_FDR2(F_lhstats.pval,F_lhstats.sgn,lhcortex,0.05,0);
fs_write_fstats(F_lhstats,mri,'sig.mgh','sig');
Thank you for your assistance
Vivian
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